/*

 * Copyright (c) 1994, 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package java.io;

/**

 * A data output stream lets an application write primitive Java data

 * types to an output stream in a portable way. An application can

 * then use a data input stream to read the data back in.

 *

 * @author  unascribed

 * @see     java.io.DataInputStream

 * @since   1.0

 */

public

class DataOutputStream extends FilterOutputStream implements DataOutput {

    /**

     * The number of bytes written to the data output stream so far.

     * If this counter overflows, it will be wrapped to Integer.MAX_VALUE.

     */

    protected int written;

    /**

     * bytearr is initialized on demand by writeUTF

     */

    private byte[] bytearr = null;

    /**

     * Creates a new data output stream to write data to the specified

     * underlying output stream. The counter {@code written} is

     * set to zero.

     *

     * @param   out   the underlying output stream, to be saved for later

     *                use.

     * @see     java.io.FilterOutputStream#out

     */

    public DataOutputStream(OutputStream out) {

        super(out);

    }

    /**

     * Increases the written counter by the specified value

     * until it reaches Integer.MAX_VALUE.

     */

    private void incCount(int value) {

        int temp = written + value;

        if (temp < 0) {

            temp = Integer.MAX_VALUE;

        }

        written = temp;

    }

    /**

     * Writes the specified byte (the low eight bits of the argument

     * {@code b}) to the underlying output stream. If no exception

     * is thrown, the counter {@code written} is incremented by

     * {@code 1}.

     * <p>

     * Implements the {@code write} method of {@code OutputStream}.

     *

     * @param      b   the {@code byte} to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public synchronized void write(int b) throws IOException {

        out.write(b);

        incCount(1);

    }

    /**

     * Writes {@code len} bytes from the specified byte array

     * starting at offset {@code off} to the underlying output stream.

     * If no exception is thrown, the counter {@code written} is

     * incremented by {@code len}.

     *

     * @param      b     the data.

     * @param      off   the start offset in the data.

     * @param      len   the number of bytes to write.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public synchronized void write(byte b[], int off, int len)

        throws IOException

    {

        out.write(b, off, len);

        incCount(len);

    }

    /**

     * Flushes this data output stream. This forces any buffered output

     * bytes to be written out to the stream.

     * <p>

     * The {@code flush} method of {@code DataOutputStream}

     * calls the {@code flush} method of its underlying output stream.

     *

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     * @see        java.io.OutputStream#flush()

     */

    public void flush() throws IOException {

        out.flush();

    }

    /**

     * Writes a {@code boolean} to the underlying output stream as

     * a 1-byte value. The value {@code true} is written out as the

     * value {@code (byte)1}; the value {@code false} is

     * written out as the value {@code (byte)0}. If no exception is

     * thrown, the counter {@code written} is incremented by

     * {@code 1}.

     *

     * @param      v   a {@code boolean} value to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeBoolean(boolean v) throws IOException {

        out.write(v ? 1 : 0);

        incCount(1);

    }

    /**

     * Writes out a {@code byte} to the underlying output stream as

     * a 1-byte value. If no exception is thrown, the counter

     * {@code written} is incremented by {@code 1}.

     *

     * @param      v   a {@code byte} value to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeByte(int v) throws IOException {

        out.write(v);

        incCount(1);

    }

    /**

     * Writes a {@code short} to the underlying output stream as two

     * bytes, high byte first. If no exception is thrown, the counter

     * {@code written} is incremented by {@code 2}.

     *

     * @param      v   a {@code short} to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeShort(int v) throws IOException {

        out.write((v >>> 8) & 0xFF);

        out.write((v >>> 0) & 0xFF);

        incCount(2);

    }

    /**

     * Writes a {@code char} to the underlying output stream as a

     * 2-byte value, high byte first. If no exception is thrown, the

     * counter {@code written} is incremented by {@code 2}.

     *

     * @param      v   a {@code char} value to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeChar(int v) throws IOException {

        out.write((v >>> 8) & 0xFF);

        out.write((v >>> 0) & 0xFF);

        incCount(2);

    }

    /**

     * Writes an {@code int} to the underlying output stream as four

     * bytes, high byte first. If no exception is thrown, the counter

     * {@code written} is incremented by {@code 4}.

     *

     * @param      v   an {@code int} to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeInt(int v) throws IOException {

        out.write((v >>> 24) & 0xFF);

        out.write((v >>> 16) & 0xFF);

        out.write((v >>>  8) & 0xFF);

        out.write((v >>>  0) & 0xFF);

        incCount(4);

    }

    private byte writeBuffer[] = new byte[8];

    /**

     * Writes a {@code long} to the underlying output stream as eight

     * bytes, high byte first. In no exception is thrown, the counter

     * {@code written} is incremented by {@code 8}.

     *

     * @param      v   a {@code long} to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeLong(long v) throws IOException {

        writeBuffer[0] = (byte)(v >>> 56);

        writeBuffer[1] = (byte)(v >>> 48);

        writeBuffer[2] = (byte)(v >>> 40);

        writeBuffer[3] = (byte)(v >>> 32);

        writeBuffer[4] = (byte)(v >>> 24);

        writeBuffer[5] = (byte)(v >>> 16);

        writeBuffer[6] = (byte)(v >>>  8);

        writeBuffer[7] = (byte)(v >>>  0);

        out.write(writeBuffer, 0, 8);

        incCount(8);

    }

    /**

     * Converts the float argument to an {@code int} using the

     * {@code floatToIntBits} method in class {@code Float},

     * and then writes that {@code int} value to the underlying

     * output stream as a 4-byte quantity, high byte first. If no

     * exception is thrown, the counter {@code written} is

     * incremented by {@code 4}.

     *

     * @param      v   a {@code float} value to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     * @see        java.lang.Float#floatToIntBits(float)

     */

    public final void writeFloat(float v) throws IOException {

        writeInt(Float.floatToIntBits(v));

    }

    /**

     * Converts the double argument to a {@code long} using the

     * {@code doubleToLongBits} method in class {@code Double},

     * and then writes that {@code long} value to the underlying

     * output stream as an 8-byte quantity, high byte first. If no

     * exception is thrown, the counter {@code written} is

     * incremented by {@code 8}.

     *

     * @param      v   a {@code double} value to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     * @see        java.lang.Double#doubleToLongBits(double)

     */

    public final void writeDouble(double v) throws IOException {

        writeLong(Double.doubleToLongBits(v));

    }

    /**

     * Writes out the string to the underlying output stream as a

     * sequence of bytes. Each character in the string is written out, in

     * sequence, by discarding its high eight bits. If no exception is

     * thrown, the counter {@code written} is incremented by the

     * length of {@code s}.

     *

     * @param      s   a string of bytes to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeBytes(String s) throws IOException {

        int len = s.length();

        for (int i = 0 ; i < len ; i++) {

            out.write((byte)s.charAt(i));

        }

        incCount(len);

    }

    /**

     * Writes a string to the underlying output stream as a sequence of

     * characters. Each character is written to the data output stream as

     * if by the {@code writeChar} method. If no exception is

     * thrown, the counter {@code written} is incremented by twice

     * the length of {@code s}.

     *

     * @param      s   a {@code String} value to be written.

     * @throws     IOException  if an I/O error occurs.

     * @see        java.io.DataOutputStream#writeChar(int)

     * @see        java.io.FilterOutputStream#out

     */

    public final void writeChars(String s) throws IOException {

        int len = s.length();

        for (int i = 0 ; i < len ; i++) {

            int v = s.charAt(i);

            out.write((v >>> 8) & 0xFF);

            out.write((v >>> 0) & 0xFF);

        }

        incCount(len * 2);

    }

    /**

     * Writes a string to the underlying output stream using

     * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>

     * encoding in a machine-independent manner.

     * <p>

     * First, two bytes are written to the output stream as if by the

     * {@code writeShort} method giving the number of bytes to

     * follow. This value is the number of bytes actually written out,

     * not the length of the string. Following the length, each character

     * of the string is output, in sequence, using the modified UTF-8 encoding

     * for the character. If no exception is thrown, the counter

     * {@code written} is incremented by the total number of

     * bytes written to the output stream. This will be at least two

     * plus the length of {@code str}, and at most two plus

     * thrice the length of {@code str}.

     *

     * @param      str   a string to be written.

     * @throws     UTFDataFormatException  if the modified UTF-8 encoding of

     *             {@code str} would exceed 65535 bytes in length

     * @throws     IOException  if some other I/O error occurs.

     * @see        #writeChars(String)

     */

    public final void writeUTF(String str) throws IOException {

        writeUTF(str, this);

    }

    /**

     * Writes a string to the specified DataOutput using

     * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>

     * encoding in a machine-independent manner.

     * <p>

     * First, two bytes are written to out as if by the {@code writeShort}

     * method giving the number of bytes to follow. This value is the number of

     * bytes actually written out, not the length of the string. Following the

     * length, each character of the string is output, in sequence, using the

     * modified UTF-8 encoding for the character. If no exception is thrown, the

     * counter {@code written} is incremented by the total number of

     * bytes written to the output stream. This will be at least two

     * plus the length of {@code str}, and at most two plus

     * thrice the length of {@code str}.

     *

     * @param      str   a string to be written.

     * @param      out   destination to write to

     * @return     The number of bytes written out.

     * @throws     UTFDataFormatException  if the modified UTF-8 encoding of

     *             {@code str} would exceed 65535 bytes in length

     * @throws     IOException  if some other I/O error occurs.

     */

    static int writeUTF(String str, DataOutput out) throws IOException {

        final int strlen = str.length();

        int utflen = strlen; // optimized for ASCII

        for (int i = 0; i < strlen; i++) {

            int c = str.charAt(i);

            if (c >= 0x80 || c == 0)

                utflen += (c >= 0x800) ? 2 : 1;

        }

        if (utflen > 65535 || /* overflow */ utflen < strlen)

            throw new UTFDataFormatException(tooLongMsg(str, utflen));

        final byte[] bytearr;

        if (out instanceof DataOutputStream) {

            DataOutputStream dos = (DataOutputStream)out;

            if (dos.bytearr == null || (dos.bytearr.length < (utflen + 2)))

                dos.bytearr = new byte[(utflen*2) + 2];

            bytearr = dos.bytearr;

        } else {

            bytearr = new byte[utflen + 2];

        }

        int count = 0;

        bytearr[count++] = (byte) ((utflen >>> 8) & 0xFF);

        bytearr[count++] = (byte) ((utflen >>> 0) & 0xFF);

        int i = 0;

        for (i = 0; i < strlen; i++) { // optimized for initial run of ASCII

            int c = str.charAt(i);

            if (c >= 0x80 || c == 0) break;

            bytearr[count++] = (byte) c;

        }

        for (; i < strlen; i++) {

            int c = str.charAt(i);

            if (c < 0x80 && c != 0) {

                bytearr[count++] = (byte) c;

            } else if (c >= 0x800) {

                bytearr[count++] = (byte) (0xE0 | ((c >> 12) & 0x0F));

                bytearr[count++] = (byte) (0x80 | ((c >>  6) & 0x3F));

                bytearr[count++] = (byte) (0x80 | ((c >>  0) & 0x3F));

            } else {

                bytearr[count++] = (byte) (0xC0 | ((c >>  6) & 0x1F));

                bytearr[count++] = (byte) (0x80 | ((c >>  0) & 0x3F));

            }

        }

        out.write(bytearr, 0, utflen + 2);

        return utflen + 2;

    }

    private static String tooLongMsg(String s, int bits32) {

        int slen = s.length();

        String head = s.substring(0, 8);

        String tail = s.substring(slen - 8, slen);

        // handle int overflow with max 3x expansion

        long actualLength = (long)slen + Integer.toUnsignedLong(bits32 - slen);

        return "encoded string (" + head + "..." + tail + ") too long: "

            + actualLength + " bytes";

    }

    /**

     * Returns the current value of the counter {@code written},

     * the number of bytes written to this data output stream so far.

     * If the counter overflows, it will be wrapped to Integer.MAX_VALUE.

     *

     * @return  the value of the {@code written} field.

     * @see     java.io.DataOutputStream#written

     */

    public final int size() {

        return written;

    }

}